Lightning and high intensity radiated field (HIRF) tolerance are critical for safe operation of aircraft in harsh environmental conditions. For instance, aircraft require continued, uninterrupted access to systems that perform functions related to flight takeoff, maintenance of flight, and landing under normal and severe HIRF conditions. Aerospace industry experience has contributed to a steady increase in the required level of lightning and HIRF tolerance for new aircraft designs, especially as more subsystems are implemented by using electronic solutions. In addition, aircraft design and construction increasingly uses non-conductive materials such as carbon fibre composites and plastics that provide less shielding than their metal predecessors increasing the need to provide HIRF tolerance.
Presently available systems for detecting lightning and HIRF are limited by the inability to form a common response, resulting in random, often contradicting identification of HIRF presence. For instance, present avionics architecture for a typical commercial airplane communications, navigation and surveillance (CNS) avionics suite is configured so that each line replaceable unit (LRU) has self-sustained HIRF and high energy radio frequency (HERF) protective circuitry. Such configuration results in each LRU reacting to HIRF differently and asynchronously depending upon LRU location, interference from adjacent systems, and each LRU's functional requirements, which leads to sporadic, unsynchronized responses. The HIRF response is ambiguous at best, as even critical systems (e.g., autopilot, landing/navigation aids, and the like) may have varying and/or unsynchronized reactions in the presence of HIRF. Thus, HIRF protection is unsynchronized amidst present avionic systems, which often results in no-fault found (NFF) and unnecessary LRU removals from the subject airplane.
Therefore, it would be desirable to provide a system and method of centralized high intensity radiated field (HIRF) detection, allowing an overall system awareness and subsequent coordinated response to the HIRF event.